Lighting the way to profitable cut-flower production: a comparative study of HPS and LED lamps in Aster sp. and Solidago canadensis

Iluminando o caminho para a produção lucrativa de flores de corte: um estudo comparativo de lâmpadas HPS e LED em Aster sp. e Solidago canadenses

Abstract

Light supplementation with HPS lamps is widely used in the production of short-day cut-flowers, such as Aster sp. and Solidago canadensis; In turn, LEDs are an affordable energy-saving alternative to replace HPS lamps, but its effectiveness in Aster sp. and S. canadensis was not studied yet. Thus, the aim of this study was to evaluate the influence of HPS and LED lamps on growth, development, flowering inhibition, and profitable value of Aster sp. and S. canadensis. For this, two assays with five hours of light supplementation were conducted, each one corresponding to one species. Aster sp. varieties were: Annency, Cirina, and White; light sources: HPS or LED lamps; and light intensities: intense or diffuse. The phenological development was not affected by light sources or intensities, with all treatments effectively inhibiting premature flowering in both species. Stem length was reduced under LED lamps in A. White, while the other growth parameters were unaffected or improved in the other varieties and species. The fewer “carnival” stems (exportation market) under LED lamps had a lower income; however, LEDs resulted in higher profits due to its lower energy consumption (47.35% lower than HPS). Therefore, LED lighting effectively inhibited premature flowering in Aster sp. and S. canadensis and maintained the quality of the cut-flowers at a lower production cost.

Keywords:
cost-benefit; phenology; high-pressure sodium lamp; light-emitting diodes; photoperiod